Dehydration in dogs

Written by Dr Andrew Miller MRCVSDr Andrew Miller MRCVS is an expert veterinary working in the field for over 10 years after graduating from Bristol University. Andy fact checks and writes for Pure Pet Food while also working as a full time veterinarian. Pure Pet FoodPure Pet Food are the experts in healthy dog food and healthy dogs featured in media outlets such as BBC, Good Housekeeping and The Telegraph. Working with high profile veterinary professionals and nutritionists, Pure Pet Food are changing dog food for the better. - Our editorial process

Your dog like any other mammal can become dehydrated when his body is losing more fluids than he is taking in or if he is not drinking enough water. Dehydration in dogs is not just a case of your pooch being thirsty, it’s actually a serious condition that can even be life-threatening.


A dog’s weight is comprised of 80% water and when he is dehydrated, he not only loses fluids but also the electrolytes such as potassium, sodium and chloride it contains which are necessary for his body to function.

A thirsty dog or a dog that is only mildly dehydrated might start to show signs of improvement after being tempted to take a drink but if you suspect your dog is more severely dehydrated it’s time to take a trip to the vet.


Top of the list when it comes to causes of dehydration in dogs is overheating and overexertion, especially during hot summer weather, this can happen to perfectly healthy dogs, because let’s face it when your pooch is having the time of his life playing with his friends the last thing he thinks of doing is stopping to take a drink. I know one of my spaniels would never drop her ball in order to do something as boring as having a drink, hence we have a ball ban going on in hot weather.

It’s good to make sure you are aware of the symptoms we’ve talked about above so you can take the appropriate action – if your dog is seriously dehydrated you need to get him to the vet and fast.

As responsible pet owners we all know that our dogs should always have access to fresh clean water, remember though that in hot weather they tend to need more, so keep an eye on your dog’s water bowls. Your pooch can’t tell you when he’s thirsty either so remember to take plenty of water on walks and regularly offer your pooch the chance to quench his thirst. It’s sensible to keep to early mornings and evenings to exercise your dog to minimise the risk.

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Some dogs just don’t drink enough even if water is readily available, especially during hot weather and senior dogs and puppies can become dehydrated more quickly. One way to try to help ensure your dog is taking in enough fluid if he is not a keen drinker is to add water to their food.

Hot weather is not the only cause though, dehydration in dogs is often a symptom of an underlying condition such as heat stroke, kidney disease, diabetes or pancreatitis. Dehydration can also occur as a result of any condition that causes your dog to lose fluids such as diarrhoea or vomiting.


There are six main signs that indicate your dog might be dehydrated and it’s good to be aware of them just in case, as a very dehydrated dog often needs to see a vet quite quickly. Let’s take a look at what they are.

  1. Your dog will probably appear lethargic and might be reluctant to move much or in severe cases have trouble walking and could maybe even collapse.

  2. Loss of appetite is a common symptom and sometimes dogs are not interested in having a drink either.

  3. Excessive panting might be one of the first symptoms you notice, panting is one way that dogs cool themselves down as they don’t sweat through their skin in the same way that we do. Dogs normally pant when they are hot or after exercise of course but if they continue to pant heavily when taking a rest, it can be an indication that your pooch is suffering from heatstroke or dehydration.

  4. Perhaps one of the simplest ways to establish if your pooch is dehydrated is to check his skin as one of the common signs of dehydration in dogs is a loss of elasticity. To check you can simply pinch some of the skin between your dog’s shoulder blades when you let go it should spring back into place immediately if the skin only returns to normal slowly or remains pinched, he is probably suffering from dehydration. The longer it takes for your dog’s skin to return to normal the more dehydrated your dog is.

  5. Another one of the common symptoms of dehydration in dogs is dry/sticky and dull gums. A well-hydrated dog’s gums are normally pink and look wet and glossy and if you gently press on them will turn white for a second before returning almost immediately to their normal pink colour. If your pooch is dehydrated his gums will stay whiter for longer because the capillaries in the gums are taking longer to refill.

  6. If your dog is very dehydrated his eyes might also appear sunken and dry.

There are some other symptoms your dog might have too, just like us if we are dehydrated your furry friend could appear irritable, he might be vomiting and or have diarrhoea and his nose and mouth might be dry, you might notice that his urine is very dark.


Sometimes mild cases of dehydration that are due to overheating or overexertion can be treated by encouraging your dog to drink, it can help to flavour their water with chicken broth or similar to tempt them. Making sure they rest inside in a cool place can help them recover too.

However, as we’ve learnt dehydration can be a very serious condition so it’s really safer to discuss their symptoms with your vet. Definitely take your pet to the vet if they are also vomiting or/and has diarrhoea, seems lethargic, or if you are worried that they look ill.

Perhaps the vet will give them some intravenous fluids or some other treatment and if there is an underlying cause you will be able to get a diagnosis and a treatment plan so that you know how to proceed.

A change of diet can play a big part in preventing dehydration caused by chronic diarrhoea or vomiting in conditions such as pancreatitis and IBS. Pure is ideal for any dog that doesn’t always drink as much as they should as it provides moisture when made up as well as excellent nutrition and as we all know – prevention is better than cure!


The best dog food for dehydration in dogs will contain plenty of moisture to help rehydrate them, and quality nutrition to restore their lost electrolytes. This means that kibble is off the cards, as it has next to no water content.

Meanwhile, Pure is a perfect dog food for dehydrated dogs as it requires water to be added to prepare the food. This makes it an excellent dinner for a thirsty dog that helps to top up their hydration levels while delivering high-quality nutrition.

Since some dogs won’t drink enough water even if it’s there in front of them, adding water into their food is an easy way to encourage them to drink (or eat) up. If your dog is dehydrated, try adding a little more water than usual to their Pure dinner to make sure they’re taking in enough liquids. Meanwhile, the natural, human-grade ingredients will help nourish your pup and restore any lost electrolytes.

Dehydration isn’t always caused by a dog not drinking, or getting too hot. Vomiting and diarrhoea often cause dehydration, meaning pups with conditions such as chronic colitis or IBS are more likely to need some help staying hydrated. The best dog food for dehydrated dogs will help to prevent illness by providing all the vitamins and minerals they need to stay healthy and maintain a strong immune system. In this case, Pure will not only provide a boost of hydration, but the short list of highly-digestible ingredients will help to prevent irritation in the gut and alleviate conditions such as colitis. Pooches like Cookie saw their hydration levels restored to normal as well as their colitis soothed by our wholesome recipes.